Miller for me, but unlike most, I don't lean as heavily on SPD and ELU as I do STR with RBs. I filter with a minimum number at SPD and STR and then sort through the guys with the highest STR. I run a heavy pass offense (currently #5 passing offense D1AA in Camp), and my slowest running back is still the #2 rusher in the conference with over 1100 yards, averaging 6.1 ypc and is #2 in D1AA in TDs with 16. He's a junior and is slower than either one of your guys (74 SPD), but has a STR of 88. My next slowest guy (still slower than both or yours) only gets sparing work with only 69 carries, but he has 500 yards rushing for a 7.2 ypc averge. Who knows what those two would do if I ran a run heavy offense.

A few seasons back under a different ID, I lost my starting DIII RB late in the season to injury and I was pretty thin at the position because I was running an offense that leaned more toward passing, so I decided to convert a SR LB that wasn't a starter and never playing to give me some RB depth. He had decent SPD for a DIII LB (low 50's as I remember), but his STR was around 80. As a converted RB, he averaged almost 250 ypg over the last 3 or 4 games of the season. Almost outrushed my injured starter in half the amount of games played, so I decided to start looking more at STR and have since.